Studies have demonstrated a high incidence of anti-SS-A and/or -SS-B antibodies in Sjogrens syndrome (SS), sicca complex (SS-sicca), and rheumatoid arthritis precipitin. (RAP) was found in high frequency in rheumatoid arthritis (RA) or SS-RA. We intend to study the relationship of these serum antibodies to disease activity, rheumatoid factor, complement or complex levels in their respective diseases. If complexes are found in these patients they will be analyzed to determine if anti-SS-A, -SS-B, RAP, and their respective antigens are present. They will also be analyzed for the presence of rheumatoid factor and if it is present, we intend to determine its binding specificity. Other studies will be designed to identify SS-A and/or SS-B antigens in saliva from patients with SS-sicca. Additionally, studies will be undertaken to test for RAP antigen in synovial fluid leucocytes and pannus layers from patients with RA. Purification of these antigens will be continued to allow more sophisticated studies to determine their role in the pathogenesis of SS and RA.